Membrane-spanning 4A genes are members of the CD20-like family. The MS4A genes are usually organized in a single genomic clusters in mammals, suggestive of gene duplication events. MS4A genes encode a class of four-transmembrane spanning proteins. MS4A genes have been described to act as a specific kind of olfactory receptor in the necklace olfactory sensory neurons in mice (Mus musculus).
In human (Homo sapiens) the members of this family include:
- MS4A1 (better known as "CD20")
- Liang Y, Buckley TR, Tu L, Langdon SD, Tedder TF (July 2001). "Structural organization of the human MS4A gene cluster on Chromosome 11q12". Immunogenetics. 53 (5): 357–68. doi:10.1007/s002510100339. PMID 11486273. S2CID 21846867.
- Greer PL, Bear DM, Lassance JM, Bloom ML, Tsukahara T, Pashkovski SL, Masuda FK, Nowlan AC, Kirchner R, Hoekstra HE, et al. 2016. A family of non-GPCR chemosensors defines an alternative logic for mammalian olfaction. Cell. 165:1734–1748. doi: 10.1016/j.cell.2016.05.001.